Recently, a touch panel for performing input in such a way to touch an input device, such as a finger or a stylus, with respect to an image displayed on a display device is applied to various electronic products.
The touch panel may be basically divided into a resistive film type touch panel and a capacitive type touch panel. The resistive film type touch panel detects a location by detecting a change in resistance according to a connection between electrodes when pressure is applied to an input device. The capacitive type touch panel detects a location by detecting a change in capacitance between electrodes when a finger touches the location. The capacitive type touch panel has recently been in the spotlight in small models by taking into consideration convenience in a manufacturing method and a sensing force.
Such a touch panel has some problems to be improved.
First, the electrode of the touch panel is electrically connected to a wire, and the wire is connected to an external circuit. In this case, the wire may be cut due to a change in the design between the electrode and the wire or a change in density. Furthermore, there may be a problem in that a conductive characteristic is deteriorated because the wire is not smoothly connected due to a crack within the electrode.
Second, in a recent electronic product, a loop type pen touch electrode for detecting input according to a stylus pen is included in a touch panel in order to use the stylus pen as input means. Since the pen touch electrode for detecting input according to the stylus pen occupies some area of the touch panel, there may be a problem in that the size of the touch panel, in particular, the size of the invalid area of the touch panel is increased.
Third, the electrode formed on the touch panel is made of a metal material. The metal material is not a transparent material, but has a unique glittering characteristic. Accordingly, there is a problem in that the visibility of the touch panel is reduced because the electrode can be externally seen.
Fourth, in general, a failure in the touch panel, such as the conduction and disconnection of the wire formed in the touch panel, is detected using touch panel test equipment. There is a problem in that the touch panel is damaged due to the touch panel test equipment because the touch panel test equipment performs a failure by touching the touch panel. Furthermore, there is a problem in that a failure generated during the fabrication process of the touch panel cannot be detected because such a failure test is performed after the fabrication of the touch panel is completed.